The present invention relates to the deformable type variable resistor element in which, when it is deformed by an external force, a number of electrical passages are formed and the current value flowing between the electrodes varies.
As this type of deformable type variable resistor element, the element employing a pressure conductive rubber material has been well known. This conductive rubber material is adapted to form a number of electrical passages by deforming the basic member made of elastic rubber material to make conductive fine particles mixed in advance in said basic member contact each other while it is adapted to discontinue the electrical passages formed by physical deformation of the basic member by separating internal conductive fine particles one from another.
Such conductive rubber material is accompanied by certain problems such that an electric conducting action, due to deformation of the basic member, that is, a resistance varying action cannot be obtained unless a force larger than the natural elastic force of rubber member which is the material for the basic member is applied to the basic member. In addition, it also accompanies a problem that the deformability is reduced and it is difficult to actuate said conductive rubber material with an extremely small external force since the repulsive elasticity of the basic member concentratively acts on a portion to which a force is applied.
The conventional pressure conductive rubber material has problems in that it produces a repulsive force against an external force because of the elasticity of said basic member and this repulsive force becomes proportionally large compared with the external force; this poses difficulties in the use of such conventional rubber materials when the external force is an impact force and the conductive rubber material is required to provide a shock absorbing effect.